I'm having trouble with a few of my homework problems this evening. *sigh*
1. Find all real solutions of x4 - 7x3 + 7x² + 21x - 30 = 0
and
2. Find a mathematical model representing the statement. (In each case determine the constant of proportionality.)
F varies directly as x and inversely as y, and F = 500 when x = 15 and y = 2
I thought number one would be easy. I guess I was wrong.
as TPH says, use the rational roots theorem. the factor theorem will also come in handy, you can look these up on wikipedia. if you still have problems, just say so
F varies directly as x means for some constant .2. Find a mathematical model representing the statement. (In each case determine the constant of proportionality.)
F varies directly as x and inversely as y, and F = 500 when x = 15 and y = 2
when F = 500, x = 15, use this to find and then plug it into the original equation to find the model.
do a similar thing with the second case, just note that F varies inversely as y means for some constant